About Biodiversity

A good place to start is the Wikipedia article or Anup Shah's Global Issues site. Briefly, biodiversity is the sum of all genes, organisms, species and ecosystems in a region. Humans depend on biodiversity for clean air, clean water and for our entire food supply. We also depend on biodiversity for our enjoyment as we visit natural places for relaxation and wonder.

Scientists accept evidence that suggests life began on Earth about 3.7 billion years ago. Though life could have had many false starts, scientists also accept evidence that life descended from a common ancestor around that time. All species alive today are thus related to this common ancestor. For about 3 billion years, life was simple -- nothing more than single-celled creatures that lived in the oceans. Then, beginning about 600 million years ago an enormous and impressive diversification known as the Cambrian explosion began. Though simple creatures still persisted, some branches of the tree of life favored complexity. 

If you explore branches in the tree of life you see that species are incredibly well adapted to their environments. Essentially the environment poses problems that life has developed solutions for (through random mutations and natural selection); species compete for their own niche in the environment. As time progressed, different groups dominated the tree of life, from fishes, to reptiles, to mammals. Despite these large changes over long evolutionary and geological times, one thing to bear in mind is that because most have their own environmental niche, most species are specialists. They are well-adapted to their particular niche so rapid changes in their environment could bring doom for the species. Once it's gone it's gone. 

Humans are mammals and are now dominating the planet in a way no species has before. Despite our efforts to preserve land in game parks and national parks, much more effort has gone into wilfully or casually altering ecosystems around the globe through clearing of land for agriculture, mining (particularly so-called mountain-top removal), pollution and the damming of rivers. These changes have had a drastic effect on Earth's biodiversity. The majority of scientists also agree that humans are altering the atmosphere by emitting carbon dioxide, through various industrial processes, including coal and oil burning, at such rapid rates that the global temperature has increased by 0.5 degrees Celsius in the past 50 years. Continued and worsening climate change will also have a disastrous effect on Earth's biodiversity. 

Scientists have catalogued some 1.8 million species but don't know if the total number is 10 million species or even more. Humans share the planet with species that descend from the same common ancestor as us. It's  their planet too. 

The time for us to educate ourselves about biodiversity and protect it is NOW. 

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